A composite ceramic-based reflective illumination light source

Abstract

The application discloses a composite ceramic-based reflective illumination light source, and relates to the technical field of illumination. The illumination light source comprises a laser, a fluorescent ceramic wafer, a base and a rotating table. The fluorescent ceramic wafer is used for emitting fluorescence and is composed of green fluorescent ceramic and red fluorescent ceramic, and is fixedly connected to the base. The laser is used for emitting laser and is arranged above the fluorescent ceramic wafer, the irradiation light of the laser is perpendicular to the fluorescent ceramic wafer, and the excitation track of the laser on the fluorescent ceramic wafer is a circle concentric with the fluorescent ceramic wafer and having a radius of 1 / 2 of the radius of the fluorescent ceramic wafer. The base is used for heat dissipation, and the rotating table is used for controlling the excitation area of the fluorescent ceramic wafer. The laser excites the rotating fluorescent ceramic wafer, the light emitting area is indirectly increased while the high brightness is maintained, the base and the ceramic color wheel are connected in a welding mode, the mechanical performance is good, the heat dissipation capacity is strong, and the saturation threshold and the light emitting intensity are higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of lighting technology, in particular to a reflection type lighting source based on composite ceramic. BACKGROUND

[0002] Laser lighting will be another revolution in the history of human lighting after incandescent lamp and fluorescent lamp, and is the development direction of the world's future lighting industry. Laser lighting source is widely used in automobile headlamps, projection light sources, marine lighting and other fields. The traditional packaging mode of fluorescent powder and organic resin is limited by low thermal conductivity (~0.1-0.4W m -1 K -1 ), and it is difficult to withstand long-term intense heat shock, and it is easy to drift in color and even carbonize at high temperature and fail, which limits the wide application of high-power laser lighting.

[0003] The paper Patterned glass ceramic design for high-brightness high-color-quality laser-driven lightings proposes a color wheel structure of glass. However, the thermal conductivity of glass is poor, the highest luminous flux is only 1000lm, the power density is only 12W / mm 2 , and the color rendering index is low, only 70. The new ceramic material with strong heat robustness and high saturation power has the characteristics of high saturation power density, and has unique advantages in spectral regulation. Fluorescent ceramic has high thermal conductivity (9-13Wm-1k-1), and the thermal conductivity can be improved by Al2O3 doping (≥20W m-1k-1), which is the first significant advantage of fluorescent ceramic. Fluorescent ceramic allows fine control of performance in different application scenarios through ion doping, microstructure design, surface state and other means, which is the second significant advantage of fluorescent ceramic. However, in the current reports, it is difficult to balance the color rendering index and luminous efficiency under the premise of meeting high power density, which is also a difficult problem for the academic and industrial circles. Therefore, it is urgent to design a fluorescent ceramic device with high saturation power density, and also with high color rendering index and luminous efficiency, to meet the lighting requirements of high-power blue LD light source. SUMMARY

[0004] In view of this, the present application discloses a reflection type lighting source based on composite ceramic, which can effectively improve the saturation power density of fluorescent material, and also has high color rendering index and luminous efficiency.

[0005] A composite ceramic-based reflective lighting source according to the purposes of the present application comprises a laser, a fluorescent ceramic disc, a base and a rotating table arranged in sequence; the fluorescent ceramic disc is used for emitting fluorescence and is fixed on the upper surface of the base; the fluorescent ceramic disc is composed of green fluorescent ceramic and red fluorescent ceramic, and the green fluorescent ceramic and the red fluorescent ceramic are arranged in a symmetrical semi-circular structure; the laser is used for emitting laser light and is arranged above the fluorescent ceramic disc, the laser light is perpendicular to the fluorescent ceramic disc, and the excitation track on the fluorescent ceramic disc is a circle concentric with the fluorescent ceramic disc and having a radius of 1 / 2 of the radius of the fluorescent ceramic disc; the base is used for heat dissipation; and the rotating table is arranged below the base and is used for controlling the excitation area of the fluorescent ceramic disc.

[0006] Preferably, the green fluorescent ceramic and the red fluorescent ceramic are adhered to the base by soldering.

[0007] Preferably, the output wavelength of the laser is 455 nm, the blue light output power is 5.0-20.0 W, and the output spot area is 0.48-0.785 mm 2 .

[0008] Preferably, the radius of the fluorescent ceramic disc is 8.0-10.0 mm, and the thickness is 0.4-1.0 mm.

[0009] Preferably, the green fluorescent ceramic is Ce-doped YAG or LuAG fluorescent ceramic, and the linear transmittance at 800 nm is 1.5-10.2%; and the red fluorescent ceramic is Ce, Mn-doped YAG or LuAG fluorescent ceramic, and the linear transmittance at 800 nm is 2.5-8.3%.

[0010] Preferably, the base is made of red copper or aluminum nitride.

[0011] Preferably, the rotating speed of the rotating table is 6500-7800 r / min.

[0012] Preferably, the luminous flux of the light source is 750-2000 lm, the luminous efficiency is 95-150 lm / W, the luminous flux density is 1562.5-3760.4 lm / mm 2 , the power density is 10.4-39.6 W / mm 2 , and the color rendering index is 80.1-85.2.

[0013] Compared with the prior art, the composite ceramic-based reflective lighting source disclosed by the present application has the following advantages:

[0014] (1) The laser excites the rotating fluorescent ceramic disc, thereby maintaining high brightness and indirectly increasing the light emitting area.

[0015] (2) The base and the ceramic color wheel are connected by welding in the application, and the mechanical performance is good, the heat dissipation capacity is strong, and the saturation threshold and the luminous intensity are higher.

[0016] (3) The fluorescent ceramic wafer in the application adopts the combination of green fluorescent ceramic and red fluorescent ceramic, and the space structure is uniformly distributed, and the color rendering index and the luminous efficiency are higher. At the same time, the green fluorescent ceramic and the red fluorescent ceramic emit light separately, avoiding the reabsorption phenomenon, and the interface light loss does not occur. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical scheme in the embodiments of the application or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0018] Figure 1 A structure diagram of a reflective illumination light source based on composite ceramic is disclosed in the application.

[0019] Figure 2 It is a blue light laser excitation trajectory.

[0020] Figure 3 A light path diagram of a reflective illumination light source based on composite ceramic is disclosed in the application.

[0021] Figure 4 It is an embodiment related illumination parameter.

[0022] In the figure: 1-laser; 2-fluorescent ceramic wafer; 20-green fluorescent ceramic; 21-red fluorescent ceramic; 3-base; 4-rotary table. DETAILED DESCRIPTION

[0023] The specific embodiments of the application will be briefly described below in combination with the drawings. Obviously, the described embodiments are only some embodiments of the application, not all embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0024] Figures 1-4 The preferred embodiments of the application are shown, and are analyzed in detail.

[0025] Embodiment 1

[0026] As Figure 1 and Figure 3The illustrated reflective lighting source based on composite ceramics includes a laser 1, a fluorescent ceramic disc 2, a substrate 3, and a rotating stage 4 arranged sequentially. The fluorescent ceramic disc 2, used for emitting fluorescence, is composed of green fluorescent ceramic 20 and red fluorescent ceramic 21, which are bonded to the substrate 3 using solder. The green fluorescent ceramic 20 and red fluorescent ceramic 21 are symmetrically arranged semi-circular structures, such as... Figure 2 As shown, laser 1 emits blue laser light and is positioned above the fluorescent ceramic disc 2. The laser beam is perpendicular to the fluorescent ceramic disc 2, and the excitation trajectory on the disc is a circle concentric with the disc and with a radius equal to half the radius of the disc. The substrate 3 is used for system heat dissipation, and a rotating stage 4 is positioned below the center of the substrate 3 to control the excitation area of ​​the fluorescent ceramic disc 2.

[0027] In this embodiment, to achieve a higher luminous efficiency, the laser 1 has an output wavelength of 455nm, a blue light output power of 5.0W, and an output spot area of ​​0.48mm. 2 The fluorescent ceramic disc 2 has a radius of 8.0 mm and a thickness of 1.0 mm. The green fluorescent ceramic 20 is a Ce-doped YAG fluorescent ceramic with a linear transmittance of 10.2% at 800 nm; the red fluorescent ceramic 21 is a Ce,Mn-doped YAG fluorescent ceramic with a linear transmittance of 8.3% at 800 nm. The substrate 3 is made of copper, and the rotating stage 4 rotates at 7800 r / min.

[0028] like Figure 4 As shown, using a constant current circuit for driving, when the laser output power is 5.0W, the luminous flux of the light source is 750lm, the luminous efficiency is 150lm / W, and the power density is 10.4W / mm². 2 The luminous flux density is 1562.5 lm / mm. 2 The color rendering index was 80.1; no luminescence saturation phenomenon was observed.

[0029] Example 2

[0030] like Figure 1 and Figure 3 The illustrated reflective lighting source based on composite ceramics includes a laser 1, a fluorescent ceramic disc 2, a substrate 3, and a rotating stage 4 arranged sequentially. The fluorescent ceramic disc 2, used for emitting fluorescence, is composed of green fluorescent ceramic 20 and red fluorescent ceramic 21, which are bonded to the substrate 3 using solder. The green fluorescent ceramic 20 and red fluorescent ceramic 21 are symmetrically arranged semi-circular structures, such as... Figure 2As shown, laser 1 emits blue laser light and is positioned above the fluorescent ceramic disc 2. The laser beam is perpendicular to the fluorescent ceramic disc 2, and the excitation trajectory on the disc is a circle concentric with the disc and with a radius equal to half the radius of the disc. The substrate 3 is used for system heat dissipation, and a rotating stage 4 is positioned below the center of the substrate 3 to control the excitation area of ​​the fluorescent ceramic disc 2.

[0031] In this embodiment, to achieve a higher luminous efficiency, the laser 1 has an output wavelength of 455nm, a blue light output power of 20.0W, and an output spot area of ​​0.785mm². 2 The fluorescent ceramic disc 2 has a radius of 10.0 mm and a thickness of 0.4 mm. The green fluorescent ceramic 20 is a Ce-doped LuAG fluorescent ceramic with a linear transmittance of 1.5% at 800 nm; the red fluorescent ceramic 21 is a Ce,Mn-doped LuAG fluorescent ceramic with a linear transmittance of 2.5% at 800 nm. The substrate 3 is made of aluminum nitride, and the rotating stage 4 rotates at 6500 r / min.

[0032] like Figure 4 As shown, using a constant current circuit for driving, when the laser output power is 20.0W, the luminous flux of the light source is 2000lm, the luminous efficiency is 100lm / W, and the power density is 25.5W / mm². 2 The luminous flux density is 2547.7 lm / mm. 2 The color rendering index is 83.2. No luminescence saturation was observed.

[0033] Example 3

[0034] like Figure 1 and Figure 3 The illustrated reflective lighting source based on composite ceramics includes a laser 1, a fluorescent ceramic disc 2, a substrate 3, and a rotating stage 4 arranged sequentially. The fluorescent ceramic disc 2, used for emitting fluorescence, is composed of green fluorescent ceramic 20 and red fluorescent ceramic 21, which are bonded to the substrate 3 using solder. The green fluorescent ceramic 20 and red fluorescent ceramic 21 are symmetrically arranged semi-circular structures, such as... Figure 2 As shown, laser 1 emits blue laser light and is positioned above the fluorescent ceramic disc 2. The laser beam is perpendicular to the fluorescent ceramic disc 2, and the excitation trajectory on the disc is a circle concentric with the disc and with a radius equal to half the radius of the disc. The substrate 3 is used for system heat dissipation, and a rotating stage 4 is positioned below the center of the substrate 3 to control the excitation area of ​​the fluorescent ceramic disc 2.

[0035] In this embodiment, to achieve higher light emitting effect, the output wavelength of the laser 1 is 455 nm, the blue light output power is 20.0 W, and the output spot area is 0.48 mm 2 . The fluorescent ceramic disc 2 has a radius of 10.0 mm and a thickness of 0.4 mm. The green fluorescent ceramic 20 is a Ce-doped LuAG fluorescent ceramic, and the linear transmittance at 800 nm is 1.5%. The red fluorescent ceramic 21 is a Ce, Mn-doped LuAG fluorescent ceramic, and the linear transmittance at 800 nm is 2.5%. The material of the substrate 3 is aluminum nitride, and the rotation speed of the rotating table 4 is 6500 r / min.

[0036] As shown in Figure 4 Figure 1 Figure 3 Figure 2 Figure 4 , when the laser output power is 19.0 W, the luminous flux of the light source is 1805 lm, the luminous efficiency is 95 lm / W, the power density is 39.6 W / mm 2 , the luminous density is 3760.4 lm / mm 2 , the color rendering index is 85.2, and a laser light source with high luminous efficiency and color rendering index is achieved.

[0037] Comparative Example

[0038] Based on Example 3, when the output power of the laser 1 is further increased to 20.0 W, the luminous flux is only 600 lm, and the luminous flux density is reduced to 1250 lm / mm 2 , and the light emitting saturation phenomenon occurs. Compared with Example 2, the excitation area of the composite ceramic is smaller, and the heat conduction heat is more concentrated. Because the heat dissipation capacity of the solder + aluminum nitride is limited, the heat cannot be continuously dissipated, the operating temperature of the ceramic is increased, the thermal quenching is caused, and the light emitting saturation phenomenon of the composite ceramic is caused.

[0039] The above description of the disclosed embodiments enables one skilled in the art to make and use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit and scope of the application. Thus, the present application is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A reflective lighting source based on composite ceramics, characterized in that, The system includes a laser (1), a fluorescent ceramic disc (2), a substrate (3), and a rotating stage (4) arranged sequentially. The fluorescent ceramic disc (2) is used to emit fluorescence and is fixed on the upper surface of the substrate (3). The fluorescent ceramic disc (2) is composed of green fluorescent ceramic (20) and red fluorescent ceramic (21), which are symmetrically arranged in a semi-circular structure. The laser (1) is used to emit laser light and is placed above the fluorescent ceramic disc (2). Its irradiation light is perpendicular to the fluorescent ceramic disc (2) and on the fluorescent ceramic disc (2). The excitation trajectory is a circle concentric with the fluorescent ceramic disc (2) and with a radius equal to half the radius of the fluorescent ceramic disc (2); the substrate (3) is used for system heat dissipation; the rotating stage (4) is located below the substrate (3) and is used to control the excitation area of ​​the fluorescent ceramic disc (2); the green fluorescent ceramic (20) and the red fluorescent ceramic (21) are respectively bonded to the substrate (3) by solder; the green fluorescent ceramic (20) is a Ce-doped YAG or LuAG fluorescent ceramic with a linear transmittance of 1.5~10.2% at 800nm; the red fluorescent ceramic (21) is a Ce, Mn-doped YAG or LuAG fluorescent ceramic with a linear transmittance of 2.5~8.3% at 800nm; the luminous flux of the light source is 750~2000 lm, the luminous efficiency is 95~150 lm / W, and the luminous flux density is 1562.5~3760.4 lm / mm 2 The power density is 10.4~39.6 W / mm². 2 The color rendering index is 80.1~85.

2.

2. The reflective lighting source based on composite ceramics according to claim 1, characterized in that, The laser (1) has an output wavelength of 455 nm, a blue light output power of 5.0~20.0 W, and an output spot area of ​​0.48~0.785 mm. 2 .

3. A reflective lighting source based on composite ceramics according to claim 1, characterized in that, The fluorescent ceramic disc (2) has a radius of 8.0~10.0 mm and a thickness of 0.4~1.0 mm.

4. A reflective lighting source based on composite ceramics according to claim 1, characterized in that, The substrate (3) is made of copper or aluminum nitride.

5. A reflective lighting source based on composite ceramics according to claim 1, characterized in that, The rotational speed of the rotary table (4) is 6500~7800 r / min.

Images